Capacitors are formed in semiconductor devices for a variety of purposes. The characteristics of a capacitor in a semiconductor device require the two conductive plates, usually comprised of polysilicon, to have certain depths. However, the non-conformity nature of the polysilicon prevents the plates from being formed in a single step. Therefore, conventional methods form a portion of the plates, add a layer of dielectric material, and form the remaining portion of the capacitor plates. The layer of dielectric material is usually deposited with a high-density plasma (“HDP”) deposition process. A chemical-mechanical polishing (“CMP”) step then follows to planarized the layer of dielectric material.
However, the CMP process often removes a portion of the dielectric layer. The unpredictability in the thickness of the dielectric layer often leads to capacitors not having the designed capacitances. In addition, the CMP process often results in non-uniformity and scratched surfaces of the dielectric layer, which will similarly affect the characteristics of the capacitors.